<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>主页面</title>
  <link rel="stylesheet" href="./css/index.css">
</head>
<body>
  <div class="box"></div>
  <section>添加了一个section标签</section>
  <ul>
    <li>aaa</li>
    <li>aaa</li>
    <li>aaa</li>
  </ul>
</body>
</html>